How to preset Blender shaders and textures?
This is actually quite easy to do: 

You can set up the .blend file that Blender default opens. 

If I wanted to set up default shaders, I would simply go to the shaders tab, and select the shader I want to be the preset.
Same goes for the textures: go to the textures tab, and select the default Blender texture I would want to be the preset.

Now comes the magical part: 

1) Save the .blend as (default.blend) or whatever.

2) Press CTRL+U to give you the "save startup file?" menu, and select it, or for the python-lovers' sake: 
bpy.ops.wm.save_homefile().

3) Re-open Blender, and discover the new changes you have made.

This is how to preset default settings in Blender (not modifiers or unset simulators), and I hope it helps all that read this post!